CNV Concordance in 1,097 MZ Twin Pairs.

Monozygotic (MZ) twins are genetically identical at conception, making them informative subjects for studies on somatic mutations. Copy number variants (CNVs) are responsible for a substantial part of genetic variation, have relatively high mutation rates, and are likely to be involved in phenotypic variation. We conducted a genome-wide survey for post-twinning de novo CNVs in 1,097 MZ twin pairs. Comparisons between MZ twins were made by CNVs measured in DNA from blood or buccal epithelium with the Affymetrix 6.0 microarray and two calling algorithms. In addition, CNV concordance rates were compared between the different sources of DNA, and gene-enrichment association analyses were conducted for thought problems (TP) and attention problems (AP) using CNVs concordant within MZ pairs. We found a total of 153 putative post-twinning de novo CNVs >100 kb, of which the majority resided in 15q11.2. Based on the discordance of raw intensity signals a selection was made of 20 de novo CNVs for a qPCR validation experiments. Two out of 20 post-twinning de novo CNVs were validated with qPCR in the same twin pair. The 13-year-old MZ twin pair that showed two discordances in CN in 15q11.2 in their buccal DNA did not show large phenotypic differences. From the remaining 18 putative de novo CNVs, 17 were deletions or duplications that were concordant within MZ twin pairs. Concordance rates within twin pairs of CNV calls with CN ≠ 2 were ~80%. Buccal epithelium-derived DNA showed a slightly but significantly higher concordance rate, and blood-derived DNA showed significantly more concordant CNVs per twin pair. The gene-enrichment analyses on concordant CNVs showed no significant associations between CNVs overlapping with genes involved in neuronal processes and TP or AP after accounting for the source of DNA.

Impact of COVID-19 Pandemic on College Student Mental Health and Wellness.

OBJECTIVE: To test the impact of the coronavirus disease 2019 (COVID) pandemic on the emotions, behavior, and wellness behaviors of first-year college students. METHOD: A total of 675 first-year university students completed a full assessment of behavioral and emotional functioning at the beginning of the spring semester 2020. Of these, 576 completed the same assessment at the end of the spring semester, 600 completed at least 1 item from a COVID-related survey after the onset of COVID pandemic, and 485 completed nightly surveys of mood and wellness behaviors on a regular basis before and after the onset of the COVID crisis. RESULTS: Externalizing problems (mean = -0.19, 95% CI = -0.06 to 0.33, p = .004) and attention problems (mean = -0.60, 95% CI = -0.40 to 0.80, p < .001) increased after the onset of COVID, but not internalizing symptoms (mean = 0.18, 95% CI = -0.1 to 0.38, p = .06). Students who were enrolled in a campus wellness program were less affected by COVID in terms of internalizing symptoms (ß = 0.40, SE = 0.21, p = .055) and attention problems (ß = 0.59, SE = 0.21, p = .005) than those who were not in the wellness program. Nightly surveys of both mood (ß = -0.10, SE = 0.03, p = .003) and daily wellness behaviors (ß = -0.06, SE = 0.03, p = .036), but not stress (ß = 0.02, SE = 0.03, p = .58), were negatively affected by the COVID crisis. The overall magnitude of these COVID-related changes were modest but persistent across the rest of the semester and different from patterns observed in a prior year. CONCLUSION: COVID and associated educational/governmental mitigation strategies had a modest but persistent impact on mood and wellness behaviors of first-year university students. Colleges should prepare to address the continued mental health impacts of the pandemic.

Assessment and etiology of attention deficit hyperactivity disorder and oppositional defiant disorder in boys and girls.

Attention deficit hyperactivity disorder (ADHD) and oppositional defiant disorder (ODD) are more common in boys than girls. In this paper, we investigated whether the prevalence differences are attributable to measurement bias. In addition, we examined sex differences in the genetic and environmental influences on variation in these behaviors. Teachers completed the Conners Teacher Rating Scale-Revised:Short version (CTRS-R:S) in a sample of 800 male and 851 female 7-year-old Dutch twins. No sex differences in the factor structure of the CTRS-R:S were found, implying the absence of measurement bias. The heritabilities for both ADHD and ODD were high and were the same in boys and girls. However, partly different genes are expressed in boys and girls.

Across the continuum of attention skills: a twin study of the SWAN ADHD rating scale.

INTRODUCTION: Most behavior checklists for attention problems or attention deficit/hyperactivity disorder (ADHD) such as the Child Behavior Checklist (CBCL) have a narrow range of scores, focusing on the extent to which problems are present. It has been proposed that measuring attention on a continuum, from positive attention skills to attention problems, will add value to our understanding of ADHD and related problems. The Strengths and Weaknesses of ADHD symptoms and Normal behavior scale (SWAN) is such a scale. Items of the SWAN are scored on a seven-point scale, with in the middle 'average behavior' and on the extremes 'far below average' and 'far above average'. METHOD: The SWAN and the CBCL were completed by mothers of respectively 560 and 469 12-year-old twin pairs. The SWAN consists of nine DSM-IV items for Attention Deficit (AD) and nine DSM-IV items for Hyperactivity/Impulsivity (HI). The CBCL Attention Problem (AP) scale consists of 11 items, which are rated on a three-point scale. RESULTS: Children who had a score of zero on the CBCL AP scale can be further differentiated using the SWAN, with variation seen between the average behavior and far above average range. In addition, SWAN scores were normally distributed, rather than kurtotic or skewed as is often seen with other behavioral checklists. The CBCL AP scale and the SWAN-HI and AD scale were strongly influenced by genetic factors (73%, 90% and 82%, respectively). However, there were striking differences in genetic architecture: variation in CBCL AP scores is in large part explained by non-additive genetic influences. Variation in SWAN scores is explained by additive genetic influences only. CONCLUSION: Ratings on the SWAN cover the continuum from positive attention skills to attention and hyperactivity problems that define ADHD. Instruments such as the SWAN offer clinicians and researchers the opportunity to examine variation in both strengths and weaknesses in attention skills.

The relations between DISC-IV DSM diagnoses of ADHD and multi-informant CBCL-AP syndrome scores.

BACKGROUND: Previous studies have examined the relation between attention problems (APs) obtained with the Child Behavior Checklist (CBCL) and attention deficit hyperactivity disorder (ADHD) assessed with the Diagnostic and Statistical Manual of Mental Disorders (DSM). We will examine this relation across sex using multi-informant data. METHODS: Parents of 12538 twins, aged 7, 10, and 12 years, and teachers of twins, aged 10 years, completed the questionnaires. The mothers of a sample of 283 boys and 291 girls who scored either low or high on longitudinal maternal CBCL-AP were interviewed. RESULTS: Children with a low AP score obtained a negative ADHD diagnosis in 96% of cases. Children with a high AP score obtained a positive diagnosis in 36% (girls) and 59% (boys) of cases. The association between paternal and maternal AP ratings and ADHD was the same, whereas the association between teacher AP ratings and ADHD was low. CONCLUSIONS: The association between AP and ADHD is higher in boys than girls, possibly because of a bias toward the male manifestation of ADHD.